Bird Facts – part 1
Senses of birds
How well can birds hear?
The hearing range of birds varies by species, but is similar to that of humans (20-20,000 hertz). Birds can still hear much better, because they can distinguish details better (greater hearing acuity). Birds are especially receptive to sounds that are the same pitch as their own.
Owls hunt with the ears.
Many owl species hear so well that they can hunt in pitch darkness. They determine the direction from which a sound comes very precisely. This is done on the basis of differences in time and intensity with which the sound of a prey animal is picked up with the left and right ear. Young owls, who have yet to learn to interpret the time difference between the left and right ear, often turn and move their heads to practice. They compare the sound they hear at the different positions of the head.
What do birds see that we don’t?
The eyes of birds resemble those of humans. Birds see light and dark with the rods in the retina. Cones ensure that birds perceive colors and have a sharp image. In addition, unlike humans, birds also see ultraviolet light and therefore experience the world very differently than we do.
Rods and cones
Night-active birds mainly have many rods (for seeing light and dark) and compensate for the lack of sharpness by a very good hearing. Day-active birds have many cones (for colors and a sharp image)
Kingfishers have a lot of red cones, because red takes the glare off the water. They can see well into the water from above. Birds that need to see well underwater to search for fish have many blue and green cones.
Birds also have cones that are sensitive to ultraviolet (UV) light. Examples of what they see with it:
- the wax coating around ripe fruits (thrushes),
- urine traces of mice (kestrels),
- the sun when it is cloudy (orientation and navigation),
- other colors in the plumage. A male blue tit / robin / magpie looks very different to those birds than a female. Feathers make the bird
Why do birds have feathers?
The main functions of springs are:
- to fly,
- retention of heat,
- repel water.
How do birds actually fly?
Birds can fly because they have several adaptations that other animals do not have:
They are therefore light and their ability to convert energy into flying power is increased.
- wings and feathers,
- thin, hollow bones,
- no heavy teeth and jaws,
- a very efficient blood circulation and respiratory system,
- a high metabolic rate.
Feather suit = rain suit
To keep feathers dry and insulating, birds often give themselves an extensive preen, which begins with a bath. They grease the feathers with an ointment from a sebaceous gland just above the tail. This makes the plumage waterproof and raindrops run off it. This keeps the bird nice and dry.
With a dust bath, excessive oil is removed from the feathers, so that they do not become too greasy. During dust bathing, a bird spins around in dust or sand, throws fine particles over its wings and body, rubs them into its plumage, and then shakes itself out again. Dust baths also help get rid of harmful parasites, such as lice and mites. Not all species take a dust bath. Sparrows do that.
Have fun watching the behavior of our birds!
Green, Play and Environment working group